When a scientist carries out an experiment or makes observations, the results are often taken as measurements. These measurements are then presented as a table. For ex ample, the results below show the growth of a baby badger. (A badger is a carnivorous mammal which is found throughout Europe and Asia.)

The growth of a baby badger from birth to the age of ten months

Age/months

Mass/kg

0

0,1

2

1,4

4

3,6

6

6,8

8

9,8

10

10,4

These results show clearly that the badger grows a lot during its first ten months. You can show these results more clearly if you draw a graph of them using graph paper.

To make a graph you must first draw two lines called axes (singular: axis). Use a sharp HB pencil and a ruler to do this. One axis is drawn horizontally across the page and the other vertically up the page.
Leave a margin next to each axis to write in.

The numbers are marked along the axis at regular intervals, for example 1, 2, 3, 4, 5, 6.

Finally you draw a line between the points and give the graph a good title :

Graphs can be useful for several reasons. Firstly, you can see very clearly that this baby badger grew very quickly up to 8 months but between eight and ten months it grew more slowly. Secondly you can use the graph to estimate, for example, the age when you would expect the baby badger to have a mass of 8kg. You draw a line from the vertical axis to the graph. At the point where this line meets the graph you draw a
vertical line down to the horizontal axis. The point where the line crosses the horizontal axis will give you the answer.

You can do the opposite. What will be the mass of the badger at 5 months?